Bug 489924

When trying to copy/move a file to an external exFAT device, like a usb drive, no matter what device it is, it will always copy it at insane and completely crazy transfer speeds like 2000 MB/s and instantly completes the transfer, showing the "Copy completed" notification. However, in reality the usb drive is actually slow, say 10 MB/s, so the files are still being copied. When you try to eject the drive, it will show "please wait, files are still being transferred...", which is correct, but will take a long time to eject because the drive is slow. This happens with any external device, the only requisite is for it to be an exFAT file system. This bug has been happening for months if not years now.

This gets very confusing because the user will erroneously think that the transfer has completed correctly, and remove the usb drive from the computer, making the file contents completely corrupted, leading to loss of what can be extremely important data. What can also happen is a change/deletion of the original file, because the user thinks it's safe to do so (because he thinks the copy is done) and that can also corrupt the original file on the destination device, because it was still being copied.

Other file managers on the same systems do not exhibit this problem, so this is a bug exclusive to Dolphin itself or one of its libraries/plugins.


STEPS TO REPRODUCE
1. Using Dolphin, copy a large file/folder from one device to another, the destination device must be an exFAT file system, the source device location/type or file system doesn't make a difference, only the target device does.
2. Notice that the transfer instantly completes or moves extremely fast in speeds that the target device could never achieve (example: a 500 MB/s transfer speed to a USB 2.0 pen drive that can in reality barely achieve 10 MB/s).
3. Dolphin shows everything successfully completed and finished. Try to eject the drive. Plasma now correctly knows something is still being transferred to the device, and tells you to wait before ejecting it: but will all users wait? Some users just remove the usb pen drives without ejecting, corrupting the contents.

OBSERVED RESULT
Transfer instantly completed and unreal extremely high speeds, when in reality it's still being processed.

EXPECTED RESULT
The transfer progress dialog showing the correct progress and speed.

SOFTWARE/OS VERSIONS
Linux: 6.8.12-200 Nobara KDE
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.2.0
Qt Version: 6.6.2